PROJECT SUMMARY Given the growing diversity of populations in the United States, communicating effectively is a key element of sexual health promotion to teens in communities where disparities exist, particularly among African American, Hispanic/Latino, American Indian/Alaska Native (AI/AN), and sexual and gender minority (SGM) youth. Disparities in sexual health outcomes suggest that these subgroups may not be receiving sufficient health information, or that messages are not perceived as relevant or understandable, impeding healthy decision-making. Understanding common and unique aspects of values, beliefs, and language should allow the crafting of messages, strategies, and steps to improve communication and contextualize sexual health promotion messages at individual and community levels. Our research will determine the preferred messages, messengers, and communication channels relevant to teens for the specific topics of abstinence, consistent and correct use of condoms, and STI/HIV testing. In response to the requested objectives in SIP 17-006, our research aims are to: (1) Conduct a literature review of barriers, facilitators, and current STI/HIV and pregnancy prevention messages and messaging channels for adolescents by race/ethnicity, sexual orientation and gender identity; (2) Conduct focus groups/interviews with African American, Hispanic/Latino, AI/AN, and SGM youth on messages, sources, and channels; (3) Conduct a Delphi survey of experts to achieve consensus on the findings of the literature review and focus groups; and (4) Conduct a second round of focus groups with a larger and broader sample of youth, to revise and finalize specific theory- and evidence-based recommendations for sexual health messaging to that meets the diversity of the adolescent population. Combining our understanding from youth (the constituent stakeholders) with input from topical experts will ensure the development of a set of recommendations that are both practical and based on evidence for acceptability and efficacy. The ultimate product will be a library of messages and strategies (including written, printed and oral sexual health messages), as well as messages delivered via mass media and multimedia technologies, organized by middle and high school age, gender, race/ethnicity, and sexual orientation and gender identity. Our approach builds upon existing collaborations and access to diverse communities, and our extensive experience as a team in adolescent sexual health promotion. It is innovative because it not only seeks to identify effective messaging in sexual health promotion, but also cultural factors influencing effectiveness.